Canon A-1 - Manual (Page 57)

AE Photography
AE photography means automatic exposure.
The camera is selecting either shutter speed
or aperture or both for you.
The most obvious, unusual feature of this
camera is the absence of the shutter speed
dial which has been replaced by the AT dial.
This dial allows you to set either shutter
speed or aperture for any of five different
AE modes.
Through-the*lens fuU-aperture metering
Shutter-speed priority AE
Aperture priority AE
Programmed .-\E
AE flash photography
Through-the-leng stopped-down metering
Stopped-down AE
In shutter-speed priority .\E, you set the
shutter speed, and the camera automatically
selects the necessary aperture according to
lighting conditions for correct exposure.
Shutter-speed priority AE is applicable to
most subjects but especially useful in action
photography.
In aperture priority AE, you set the aperture
while the camera automatically selects the
necessary shutter speed for correct exposure.
It is convenient for the various forms of still
photography in which depth of field is of
importance.
The camera automatically selects both
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